I have two "aging" BOB swaps where I sent books and have not yet received the books I requested from the other boxer. Checking today, I see that both of the senders are no longer members of PBS.

I was able to PM them. Will they receive my messages through PBS even though they are no longer members?

This is very aggravating. One of the members had an address that I could not get DC for and that made me suspicious even though she told me that she had gotten lots of books delivered to the address with and without DC.

My other BOB was delivered to the recipient on 6/28/07 according to the PBS DC record.

Both pending BOB's were marked mailed - one on 6/28/07 and the other on 7/3/07 - however, I have not received them.

Am I correct in assuming there is nothing that can be done about a BOB swap where one party does not receive the books?

In general, things can be done when both parties are reasonable people. I've had a few cases where boxes I sent went missing; I offer to let the other member pick another set of books. Other members have offered the same to me.

In some cases, if there appears to be a pattern of abuse R&R may revoke their membership... hm...

I've also had a few cases of BOB partners "no longer a member". I sent a message to R&R with the trade details and asked them to cancel out the BOB trade so it would stop cluttering up my account.